Player and user safety is becoming much more important in hockey, and related sports and activities in ice rinks or the like. There have been many desirable proposals for accomplishing this, such as in U.S. Pat. Nos. 7,914,385, 8,696,478, 9,091,091, and 9,283,469, and Canadian 2708199. The invention seeks to take advantage of many of the desirable features of the above proposals, and to take a whole rink concept that will provide maximum protection to the players and users who might impact the side walls/dasher boards of the rink.
A significant feature of the invention is that it decouples the facing or moving portions of the walls/dasher boards from the heavy support structures. For example according to one aspect of the invention the dasher boards can actually move over the ice surface when impacted. According to another aspect, an off-the-ice support structure is provided so that only the facing moves upon impact. While in U.S. Pat. No. 9,091,091 an energy absorbing sports board assembly is provided that is not fixed to the floor of the arena but can move with respect to it, the structure provided includes a ramp and catch plate so that the relative movement of the board assembly is not actually on the surface of the arena and requires the movement of the entire heavy support structure. Also, the movement has a vertical component in addition to a horizontal one, which may be undesirable in some circumstances. These drawbacks are avoided according to the invention which provides a simple and effective system that utilizing almost exclusively horizontal movement and optimum safety for players and users.
According to another feature of the invention, roller or sliding elements are provided that can move in channels that allow a large deflection of dasher boards or the like around the periphery of a rink or other arena, perhaps even a deflection of as much as two feet.
According to one aspect of the invention a movable dasher board system is provided comprising: A bottom structure having low friction characteristics. A dasher board assembly operatively connected to and extending upwardly from the bottom structure. And biasing and impact force absorbing devices which bias the bottom structure and dasher board assembly to a desired position and upon movement of the bottom structure absorb the impact of a human hitting the dasher board assembly to minimize the possibility of injury to the human.
The bottom structure may comprise a bottom surface that is of any suitable material that itself has low friction characteristics, or the bottom surface may be coated with or operatively connected to a low friction material. For example the bottom surface may be a sliding surface (e.g. a plate or block) selected from the group consisting essentially of steel, acetal (e.g. Delrin®), and polytetrafluoroethylene (e.g. Teflon®), or a metal coated on the bottom thereof with polytetrafluoroethylene or acetal, or a metal structure operatively attached to a plate or sheet of acetal or polytetrafluoroethylene. For example many steels have a static coefficient of friction (μs) with respect to ice of 0.03 while polytetrafluoroethylene has a μs with respect to itself of 0.04 and a μs of 0.02 with respect to ice that is dry, while acetal has a μs with respect to itself of 0.06 and an even lower μs with respect to ice [source: engineeringtoolbox.com; or “Friction Science and Technology” by Blau, Fundamentals of Sliding Friction, page 145]. Desirably the bottom surface has a μs of about 0.1 or less (preferably 0.05 or less, most preferably about 0.02-0.03) with respect to ice that is dry.
Typically, the bottom surface engages ice and the dasher board assembly slides with respect to the ice when impacted by a human, and under the bias of the bias and impact force absorbing devices. Alternatively the bottom surface may instead ride in a channel of metal or hard plastic, or may simply move on a sheet or plate or block of a material having low friction characteristics similar to the bottom surface.
Alternatively, the bottom structure low friction characteristics may be provided by a plurality of rollers, for example which provide an effective coefficient of rolling friction 0.04 or less (e.g. about 0.01). Suitable commercial rollers are available from SKF USA Inc. of Lansdale, Pa., Schaeffler Group of Herzogenaurach, Germany, and many other companies, and the basic concepts thereof are shown in U.S. Pat. No. 808,500.
The dasher board assembly may comprise a typical dasher board, such as shown in a number of the above-mentioned patents, having a bottom portion of HDPE or the other materials listed in U.S. Pat. Nos. 8,696,478 and 7,914,385, and an upper transparent material portion such as acrylic or the other materials listed in U.S. Pat. Nos. 8,696,478 and 7,914,385.
The biasing and impact force absorbing devices may comprise a wide variety of mechanisms such as telescoping tubes (e.g. pneumatic or hydraulic pistons, or those with internal springs), foam, gel, compression springs, or the like. Normally the biasing and absorbing devices simply act between the bottom portions of the dasher board assemblies and a stationary exterior wall or the like, but they can also be provided at the upper portions of dasher board assemblies.
The system of the invention can either be installed indoors in a new arena, stadium, soccer facility, or other sport or activity area that has a history of injury from impacts on structures defining the playing/use surface. It may also be installed in any outdoor sports facility, with spectator and/or support areas exterior thereof, or it may be retrofit into existing facilities. When retrofit into existing facilities an ice rink may lose about 6-16 inches around the entire periphery in order to accommodate the new dasher board assemblies, bottom structures, and biasing and impact force absorbing devices. The embodiment of the invention which sits off the ice can be retrofit into just the ends or corners of the rink as this is where more than 75% of the severe and catastrophic injuries occur.
In situations where the rink or arena area is better suited to have a moving system outside of the ice surface then as long as some other low friction material is provided at the position to which a sliding bottom structure is normally biased, the desired features of the invention will still be accomplished. For example polytetrafluoroethylene has a μs with respect to itself of 0.04, while acetal has a μs with respect to itself of 0.06 so polytetrafluoroethylene or acetal bottom structures (such as plates) sliding on acetal or polytetrafluoroethylene floor areas will function nicely (e.g. a μs of about 0.1 or less). Alternatively the low friction features of the bottom structure may utilize roller bearings which move in a metal or plastic channel or on a surface, and the rollers may have an effective coefficient of rolling friction 0.04 or less.
According to another aspect of the present invention there is provided a movable dasher board system comprising: a mounting frame having upper and bottom structures having low friction characteristics; a dasher board assembly operatively connected to the mounting frame; and biasing and impact force absorbing devices which bias the mounting frame and dasher board assembly to a desired position and upon movement of the frame absorb the impact of a human hitting the dasher board assembly to minimize the possibility of injury to the human. The upper and bottom structures may comprise sets of rollers which provide an effective coefficient of rolling friction 0.04 or less, or alternatively may comprise sliding elements having a μs of about 0.1 or less on the surfaces on which they slide. The rollers or sliding elements may roll or slide in channels of metal or plastic. The bias and impact force absorbing devices are as described above, e.g. telescoping tubes.
According to a still another aspect of the invention there is provided a method of protecting human participant safety in a rink or arena by providing around the exterior of the playing or use surface of the rink or arena a movable dasher board system including a bottom structure having low friction characteristics, a dasher board assembly operatively connected to the bottom structure, and biasing and impact force absorbing devices which bias the bottom structure and dasher board assembly to a desired position and upon movement of the bottom structure absorb the impact of a human hitting the dasher board assembly to minimize the possibility of injury to the human.
It is the primary object of the present invention to provide an enhanced safety system, and method, for hockey rinks or other arenas or activities; this and other objects of the invention will become clear from a detailed description of the invention and from the appended claims.